Sensitive quantitation of ultra-trace toxic aconitines in complex matrices by perfusion nano-electrospray ionization mass spectrometry combined with gas-liquid microextraction

The accurate analysis of ultra-trace (e.g. <10-4 ng/mL) substances in complex matrices is a burdensome but vital problem in pharmaceutical analysis, with important implications for precise quality control of drugs, discovery of innovative medicines and elucidation of pharmacological mechanisms. Herein, an innovative constant-flow perfusion nano-electrospray ionization (PnESI) technique was developed firstly features significant quantitative advantages in high-sensitivity ambient MS analysis of complex matrix sample. More importantly, double-labeled addition enrichment quantitation strategies of gas-liquid microextraction (GLME) were proposed for the first time, allowing highly selective extraction and enrichment of specific target analytes in a green and ultra-efficient (>1000-fold) manner. Using complex processed Aconitum herbs as example, PnESI-MS directly enabled the qualitative and absolute quantitative analysis of the processed Aconitum extracts and characterized the target toxic diester alkaloids with high sensitivity, high stability, wide linearity range, and strong resistance to matrix interference. Further, GLME device was applied to obtain the highly specific enrichment of the target diester alkaloids more than 1000-fold, and accurate absolute quantitation of trace aconitine, mesaconitine, and hypaconitine in the extracts of Heishunpian, Zhichuanwu and Zhicaowu was accomplished (e.g., 0.098 pg/mL and 0.143 pg/mL), with the quantitation results well below the LODs of aconitines from any analytical instruments available. This study built a systematic strategy for accurate quantitation of ultra-trace substances in complex matrix sample and expected to provide a technological revolution in many fields of pharmaceutical research.

Anti-rheumatic potential vis-à-vis aconitine and hypaconitine content analysis in different Aconitum spp. from Sikkim Himalayas (India)

Aconitum spp. are important medicinal plants mentioned in Ayurveda as Ativisa or Vatsanabha. The present study aims to evaluate anti-rheumatic potential in seven Aconitum species and correlation with aconitine and hypaconitine content. Anti-rheumatic potential was analyzed through in vitro xanthine oxidase inhibition, anti-inflammatory and ROS scavenging assays; and quantification of aconitine and hypaconitine with RP-HPLC method validated as per ICH guidelines. The findings reveal that A. palmatum possessed the most promising response (IC50 =12.68±0.15 μg/ml) followed by A. ferox (IC50 =12.912±1.87 μg/ml) for xanthin oxidase inhibition. We observed a wide variation in aconitine and hypaconitine content ranging from 0.018 %-1.37 % and 0.0051 %-0.077 % respectively on dry weight basis. Aconitine and hypaconitine showed moderate positive correlation (r=0.68 and 0.59 respectively) with anti-rheumatic potential. The study identifies potential alternative species of Aconitum that can help in sustainable availability of quality raw material.

[Differences in chemical components in processing of dried ginger-steamed, sand-fried, and rice swill water-bleached Aconiti Lateralis Radix Praeparata pieces in "Jianchang" faction based on UPLC-MS/MS]

This study compared the changes in chemical components during the processing of different types of Aconiti Lateralis Radix Praeparata(ALRP) in "Jianchang" faction, i.e., dried ginger-steamed ALRP pieces(Yin-FP), sand-fried ALRP pieces(Yang-FP), and rice swill water-bleached ALRP pieces(DFP), and provided a scientific basis for the mechanism in toxicity reduction and efficacy enhancement from a compositional perspective. Samples were collected during the processing of the three types of ALRP pieces, yielding raw ALRP pieces, water-bleached Yin-FP, ginger juice-moistened Yin-FP, steamed Yin-FP, water-bleached Yang-FP, sand-fried Yang-FP, water-bleached DFP, rice swill water-bleached DFP, and roasted DFP. Aconitine, mesaconitine, hypaconitine, benzoylaconine, benzoylmesaconine, benzoylhypaconine, aconine, mesaconine, hypaconine, salsolinol, fuziline, and higenamine in the extracts were determined by UPLC-MS/MS, and then content analysis and cluster heatmap analysis were performed on 11 sets of samples. During the processing of the three types of ALRP pieces, bleaching significantly reduced the content of 12 alkaloids; steaming, stir-frying, and roasting significantly reduced the content of diester-type alkaloids(aconitine, mesaconitine, and hypaconitine) and significantly increased the content of monoester-type alkaloids(benzoylaconine, benzoylmesaconine, and benzoylhypaconine) and aminoalcohol-type alkaloids(aconine, mesaconine, and hypaconine). During the processing of Yin-FP, the diester-type alkaloids continuously decreased, while the monoester-type and aminoalcohol-type alkaloids showed an initial decrease followed by an increase. During the processing of Yin-FP, Yang-FP, and DFP, the diester-type alkaloids continuously decreased, while the monoester-type and aminoalcohol-type alkaloids showed an initial decrease followed by an increase. Steamed Yin-FP showed a higher increase in content than fried Yang-FP and roasted DFP. Comprehensive analysis of content differences in toxic and therapeutic components in three ALRP pieces suggests that the distinctive processing methods in "Jianchang" faction can indeed achieve detoxification and efficacy enhancement on ALRP. This study provides references for understanding the mechanisms of action of the three processing methods.

Analysis of the pharmacodynamic difference between Xiaojin Pills taken with Chinese Baijiu and water based on serum pharmacochemistry and pharmacokinetics

ETHNOPHARMACOLOGICAL RELEVANCE

Xiaojin Pills (XJPs), which has the function of dissipating knots and dispersing swelling, removing blood stasis, and relieving pain, is a classic prescription for the treatment of mammary glands hyperplasia. It is also the first choice of Chinese patent medicine for the clinical treatment of mammary glands hyperplasia in contemporary traditional Chinese medicine clinics. Previous studies have shown that the efficacy of XJPs "taken orally after soaked with Chinese Baijiu" in tradition was significantly better than that of taking it orally with water in modern in terms of activating the blood, anti-inflammation, analgesia, anti-mammary gland hyperplasia, anti-breast cancer and its metastasis in vitro and in vivo, especially under low-dose conditions. However, the material basis for the difference in efficacy between XJP&B and XJP&W is still unclear.

AIM OF THE STUDY

To analyze the material basis of the significant difference in efficacy between XJP&B and XJP&W from the perspective of serum pharmacochemistry and pharmacokinetics, and clarified the scientific connotation of XJPs "taken orally after soaked with Chinese Baijiu".

MATERIALS AND METHODS

Ultra-high performance liquid chromatography-mass spectrometry combined with a multivariate statistical analysis method were used to screen the differential components in the Chinese Baijiu extract and the water extract of XJPs and the corresponding residues, so as to clarify the differential components between XJP&B and XJP&W in vitro. The migrating components in the blood after XJP&B and XJP&W were characterized by serum pharmacochemical methods, in order to clarify the differential components in rats. The pharmacokinetic parameters of the representative components absorbed into the blood were compared between XJP&B and XJP&W by the pharmacokinetics study method, in order to determine the dynamic changes of the representative components in rats.

RESULTS

The identification results of different components in vitro showed that there were 34 and 12 different compounds between the Chinese Baijiu extract and water extract of XJPs, and the residues after Chinese Baijiu extraction and water extraction, respectively. The content of different components such as arachidonic acid, ursolic acid, 3-acetyl-11-keto-β-boswellic acid, 2α-hydroxyursolic acid, and oleanolic acid was higher in the Chinese Baijiu extract, which was more than twice the content in the water extract. The results of the serum pharmacochemistry study indicated that 42 prototype components were identified in the serum of rats after XJP&B and XJP&W, including organic acids, alkaloids, steroids, and terpenoids. And XJP&B increased the absorption of the prototype components of organic acids in XJPs into the blood. The pharmacokinetic study results of representative components demonstrated that the mean plasma concentration-time profile and pharmacokinetic parameters of muscone, aconitine, and 3-acetyl-11-keto-β-boswellic acid were significantly different between XJP&B and XJP&W. Compared with XJP&W, the C_max and AUC_0-t of muscone and aconitine in XJP&B were higher, and the T_1/2 and MRT_0-t of 3-acetyl-11-keto-β-boswellic acid in XJP&B were relatively longer.

CONCLUSION

This research proved that "taking XJPs orally after being soaked with Chinese Baijiu" can increase the dissolution and absorption of active ingredients in XJPs, increase the plasma concentration and content of representative ingredients, and prolong its action time, thus enhancing the biological activity of XJPs in vitro and in vivo. To a certain extent, this study revealed the material basis of the significantly better efficacy of XJP&B than XJP&W and clarified the scientific connotation of XJPs "taken orally after soaked with Chinese Baijiu", which can provide a theoretical basis for the optimization of XJPs' clinical administration method.

Identification and quantification of eight alkaloids in Aconitum heterophyllum using UHPLC-DAD-QTOF-IMS: A valuable tool for quality control

INTRODUCTION

Aconitum spp. are prime medicinal plants rich in alkaloids and have been used as the main constituents of traditional medicine in India and China. The whole plant can be toxic and creates pathophysiological conditions inside the human body. Therefore, simultaneous quantification of alkaloids within plant parts and herbal medicines associated with this genus is essential for quality control.

OBJECTIVE

We aimed to develop and validate methods using ultra-high-performance liquid chromatography-diode array detector-quadrupole time-of-flight ion mobility mass spectrometry (UHPLC-DAD-QTOF-IMS) and to develop an analytical strategy for the identification and quantification of alkaloid compounds (aconitine, hypaconitine, mesaconitine, aconine, benzoylmesaconitine, benzoylaconine, bulleyaconitine A, and deoxyaconitine) from Aconitum heterophyllum.

METHODOLOGY

We developed a simultaneous identification and quantification method for eight alkaloids using UHPLC-DAD-QTOF-IMS. The method was validated as per International Council for Harmonization of Technical Requirements for Pharmaceuticals for Human Use (ICH) guidelines and also in IMS mode.

RESULTS

The developed method has good linearity (r²  = 0.997-0.999), LOD (0.63-8.31 μg/mL), LOQ (0.63-2.80 μg/mL), recovery (86.01-104.33%), reproducibility, intra- and inter-day variability (<3.25%), and stability. Significant qualitative and quantitative variations were found among different plant parts (flower, leaf, stem, root, and tuber) and five market products of A. heterophyllum. Furthermore, a total of 21 metabolites were also profiled based on the fragmentation pattern of MS² using the validated method.

CONCLUSION

An appropriate mobile phase using acetonitrile and water in a gradient elution gave a satisfactory chromatographic separation of eight Aconitum alkaloids with their adjacent peaks. Therefore, this method could provide a scientific and technical platform for quality control assurance.

Aconitum Diterpenoid Alkaloid Profiling to Distinguish between the Official Traditional Chinese Medicine (TCM) Fuzi and Adulterant Species Using LC-qToF-MS with Chemometrics

The lateral roots of Aconitum carmichaelii, known in Chinese as fuzi, are officially recognized as a materia medica in the Chinese Pharmacopoeia and used culinarily to prepare herbal soups. A strategy combining UPLC-qToF-MS analysis of A. carmichaelii and its intraspecies and interspecies chemometrics study was developed to examine the distribution of Aconitum marker metabolites. Four diterpenoid alkaloids were recognized to be important markers in fuzi, and another 15 markers were identified to differentiate A. carmichaelii from adulterant species. The detected fuzi markers, mesaconitine (47) and hypaconitine (51), are known to be the principal toxins in this herb, while fuziline (6) and benzoylmesaconine (25) are associated with its medicinal properties. Additional marker compounds have been detected in other Aconitum species that are useful for identifying adulteration. This study provides a useful resource for detecting traditional Chinese medicine (TCM) adulterants and assisting in the quality control of botanical products in TCM and beyond.

Pharmacokinetics-based chronoefficacy of Fuzi against chronic kidney disease

OBJECTIVES

Identifying drugs with time-varying efficacy or toxicity, and understanding the underlying mechanisms would help to improve treatment efficacy and reduce adverse effects. In this study, we uncovered that the therapeutic effect of Fuzi (the lateral root of Aconitum carmichaelii Debeaux) depended on the dosing time in mice with adenine-induced chronic kidney disease (CKD).

METHODS

The Fuzi efficacy was determined by biomarker measurements [i.e. plasma creatinine (CRE), blood urea nitrogen (BUN) and urinary N-acetyl-β-D-glucosaminidase (NAG)], as well as inflammation, fibrosis and histological analyses. Circadian regulation of Fuzi pharmacokinetics and efficacy was evaluated using brain and muscle Arnt-like protein-1 (Bmal1)-deficient (Bmal1-/-) mice.

KEY FINDINGS

The Fuzi efficacy was higher when the drug was dosed at ZT10 and was lower when the drug was dosed at other times (ZT2, ZT6, ZT14, ZT18 and ZT22) according to measurements of plasma CRE, BUN and urinary NAG. Consistently, ZT10 (5 PM) dosing showed a stronger protective effect on the kidney (i.e. less extensive tubular injury) as compared to ZT22 (5 AM) dosing. This was supported by lower levels of inflammatory and fibrotic factors (IL-1β, IL-6, Tnf-α, Ccl2, Tgfb1 and Col1a1) at ZT10 than at ZT22. Pharmacokinetic analyses showed that the area under the curve (AUC) values (reflective of systemic exposure) and renal distribution of aconitine, hypaconitine and mesaconitine (three putative active constituents) for Fuzi dosing at ZT10 were significantly higher than those for herb dosing at ZT22, suggesting a role of circadian pharmacokinetics in Fuzi chronoefficacy. Drug efficacy studies confirmed that aconitine, hypaconitine and mesaconitine possessed a kidney-protecting effect. In addition, genetic knockout of Bmal1 in mice abolished the time-dependency of Fuzi pharmacokinetics and efficacy. This reinforced the existence of chronoefficacy for Fuzi and supported the role of circadian pharmacokinetics in Fuzi chronoefficacy.

CONCLUSIONS

The efficacy of Fuzi against CKD depends on the dosing time in mice, which is associated with circadian pharmacokinetics of the three main active constituents (i.e. aconitine, hypaconitine and mesaconitine). These findings highlight the relevance of dosing time in the therapeutic outcomes of herbal medicines.

Supramolecular structure, in vivo biological activities and molecular-docking-based potential cardiotoxic exploration of aconine hydrochloride monohydrate as a novel salt form

Despite the high profile of aconine in WuTou injection, there has been no preparative technology or structural studies of its salt as the pharmaceutical product. The lack of any halide salt forms is surprising as aconine contains a tertiary nitrogen atom. In this work, aconine was prepared from the degradation of aconitine in Aconiti kusnezoffii radix (CaoWu). A green chemistry technique was applied to enrich the lipophilic-poor aconine. Reaction of aconine with hydrochloride acid resulted in protonation of the nitrogen atom and gave a novel salt form (C₂₅H₄₂NO₉⁺·Cl^-·H₂O; aconine hydrochloride monohydrate, AHM), whose cation in the crystal structure was elucidated based on extensive spectroscopic and X-ray crystallographic analyses. The AHM crystal had a Z' = 3 structure with three independent cation-anion pairs, with profound conformational differences among the aconine cations. The central framework of each aconine cation was compared with that of previously reported aconitine, proving that protonation of the nitrogen atom induced the structure rearrangement. In the crystal of AHM, aconine cations, chloride anions and water molecules interacted through inter-species O-H...Cl and O-H...O hydrogen bonds; this complex hydrogen-bonding network stabilizes the supramolecular structure. The seriously disordered solvent molecules were treated using the PLATON SQUEEZE procedure [Spek (2015). Acta Cryst. C71, 9-18] and their atoms were therefore omitted from the refinement. Bioactivity studies indicated that AHM promoted in vitro proliferative activities of RAW264.7 cells. Molecular docking suggested AHM could target cardiotoxic protein through the hydrogen-bonding interactions. The structural confirmation of AHM offers a rational approach for improving the pharmaceutical technology of WuTou injection.

Optimization of the traditional processing method for precision detoxification of CaoWu through biomimetic linking kinetics and human toxicokinetics of aconitine as toxic target marker

ETHNOPHARMACOLOGICAL RELEVANCE

CaoWu (Aconiti Kusnezoffii Radix), well known for its high toxicity leading to fatal ventricular arrhythmias, is detoxified by HeZi (Terminalia Chebula Retz) decoction to prepare ZhiCaoWu (Aconiti Kusnezoffii Radix Preparata) as one part of ingredients of NaRu-3 pill which is used for the treatment of rheumatoid arthritis (RA). Aconitine (AC) is a highly toxic alkaloid of CaoWu and it is used as toxic target marker for the quality control (QC) of ZhiCaoWu. In the traditional processing method, the vanish of astringent or spicy feeling in tongue is the important detoxification indicator of ZhiCaoWu. However, how CaoWu is detoxified to ZhiCaoWu and whether the appropriate content of AC in ZhiCaoWu can be efficiently perceived after the empirical detoxification still lack factual basis.

AIM OF THE STUDY

The present study aimed to optimize the traditional processing method for precision detoxification of CaoWu through biomimetic linking kinetics and human toxicokinetics (TK) of AC, with a view of providing insights into the changes of toxic target marker.

MATERIALS AND METHODS

CaoWu medicinal slices (Mes) and coarse powder (Cop) were processed by blank HeZi decoction through the soaking method for 7 days. High-performance liquid chromatography (HPLC) was used for the analysis of the samples. The acidity of blank HeZi decoction and HeZi processing decoction was directly determined by pH meter. The non-compartment analysis (NCA) was used to have an intuitive appreciation for AC and pH changes in HeZi processing decoction while the compartment model method was used to build the biomimetic linking kinetics model with the covariate. The inter-species scaling of animal TK parameters was conducted to predict human AC TK profiles. The possible uptake ways of AC (rapid-release or extended-release) for humans were attempted to assess the poisoning risk of AC in NaRu-3 pill. Based on the target content of AC in ZhiCaoWu, the biomimetic linking kinetics model was explored to optimize the traditional processing detoxification method of CaoWu. The assays of determining inflammatory cytokines in lipopolysaccharides (LPS)-induced RAW264.7 cells were performed to investigate the inflammatory modulation effects of AC in vitro.

RESULTS

ZhiCaoWu was prepared by eliminating redundant AC in CaoWu through the repeatable replacement of HeZi processing decoction in which its acidity (pH) was affected. AC-pH changes in HeZi processing decoction were adequately depicted by a biomimetic linking kinetics model whose predictive power was determined by comparing the predictions of AC in ZhiCaoWu with the reported data. Rapid-release AC at the converted dose of 111.1 and 417.6 μg (0.011 and 0.042% of AC in NaRu-3 pill) reached maximum blood concentrations of 26.1 and 98.1 ng/mL at 0.3 h, in comparison with minimum human lethal concentration (100 ng/mL). Achieving the target content of AC (0.04%) in ZhiCaoWu or AC (0.011%) in NaRu-3 pill to precisely control the poisoning risk, the potential optimized protocols were that the processing time at 0.2-0.8% of AC in CaoWu was 2.0-4.4 days for Cop and 2.7-6.2 days for Mes. Correspondingly, pH values in HeZi processing decoction were 3.95 and 3.77 for Cop and Mes, respectively. Meanwhile, Lipopolysaccharides (LPS)-induced RAW264.7 cells were exposed to 0, 20, and 200 μM of AC for 12 h and AC at 20 μM enhanced the levels of IL-6, IL-10 and TNF-α.

CONCLUSIONS

Thus, for the first time, a biomimetic linking kinetics model was built to optimize the traditional detoxification method. Moreover, pH changes could be developed as surrogate endpoint for guiding the processing detoxification of CaoWu. Notably, setting the content limit of AC (0.011%) was very rational to control the poisoning risk of NaRu-3 pill. In addition, it was possible that there existed the more complex mechanisms of AC for inflammatory modulation in vitro.

Research on Q-markers of Qiliqiangxin capsule for chronic heart failure treatment based on pharmacokinetics and pharmacodynamics association

BACKGROUND

Qiliqiangxin capsule (QLQX), composed of 11 herbs, is an effective traditional Chinese medicine (TCM) that has been widely used for treatment of chronic heart failure (CHF) in China. In the Chinese pharmacopoeia (Ch.P.) only astragaloside was described as the marker component to control the quality of QLQX, which could not reflect the overall effectiveness.

PURPOSE

The aim of this work was to investigate the quality markers (Q-markers) of QLQX based on the association of the pharmacodynamics (PD) of inhibitory effect on activated renin-angiotensin-aldosterone system (RAAS) and the pharmacokinetics (PK) of bioactive compounds according to the Q-marker theory.

METHODS

The contents of astragaloside, calycosin-7-glucoside, sinapine, ginsenoside Rb1, ginsenoside Rb2, ginsenoside Rg1, salvianolic acid A, salvianolic acid B, danshensu, rosmarinic acid, formononetin, aconitine, mesaconitine, hypaconitine, benzoylaconine, benzoylmesaconine and benzoylhypacoitine were determined by an HPLC-MS/MS method both in QLQX preparation and in the plasma of CHF rats administered intragastrically with QLQX. The effect of lowering angiotensin II (Ang II) production by QLQX was assayed by ELISA. The association between PK and PD was explored and the bioactive compounds with higher content in vitro and better exposure in vivo, which were closely related to the inhibitory effect on the activated RAAS, were identified as Q-markers of QLQX for CHF treatment.

RESULTS

The contents of 17 constituents were in the order of salvianolic acid B > danshensu > ginsenoside Rb1 > sinapine > benzoylmesaconine > astragaloside > benzoylhypacoitine > ginsenoside Rb2 > salvianolic acid A > ginsenoside Rg1 > calycosin-7-glucoside > rosmarinic acid > formononetin > benzoylaconine > hypaconitine > aconitine > mesaconitine in QLQX preparation. PK and PD association study of 14 bioactive compounds of QLQX showed the maximum effect (E_max) of astragaloside, calycosin-7-glucoside, sinapine and ginsenoside Rg1 and their peak concentration (C_max) appeared at the same time; while the time of E_max of ginsenoside Rb1, ginsenoside Rb2, salvianolic acid A, salvianolic acid B, danshensu, rosmarinic acid, formononetin, benzoylaconine, benzoylmesaconine and benzoylhypacoitine was delayed from the time of their C_max.

CONCLUSIONS

Astragaloside, calycosin-7-glucoside, sinapine and ginsenoside Rg1 are suitable as the Q-markers of QLQX for CHF treatment, which have higher content in vitro, finer exposure in vivo and a direct correlation with the inhibitory effect on activated RAAS.

[CHROMATOSPECTROPHOTOMETRIC METHOD OF QUANTITATIVE ANALYSIS OF LAPPACONITINE IN THE UNDERGROUND PARTS OF ACONITUM ORIENTALE MILL, GROWING IN GEORGIA]

Aconitum orientale Mill (family Helleboraceae) is a perennial herb. It is spread in forests of the west and the east Georgia and in the subalpine zone. The research objects were underground parts of Aconitum orientale Mill, which were picked in the phase of fruiting in Borjomi in 2014. We had received alkaloids sum from the air-dry underground parts (1.5 kg) with chloroform extract which was alkalined by 5% sodium carbonate. We received the alkaloids sum of 16.5 g and determined that predominant is pharmacologically active diterpenic alkaloid - Lappaconitine, which is an acting initial part of the antiarrhythmic drug "Allapinin". The chromatospectrophotometrical method of quantitative analysis of Lappaconitine is elaborated for the detection of productivity of the underground parts of Aconitum orientale Mill. It was determined that maximal absorption wave length in ultra-violet spectrum (λmax) is 308 nm; It is established that relative error is norm (4%) from statical processing of quantitative analysis results. We determined that the content of Lappaconitine in the underground parts of Aconitum orientale Mill is 0.11-0.13% in the phase of fruiting. In consequence of experimental data Aconitum orientale Mill is approved as the raw material to receive pharmacologically active Lappaconitine.

A novel concept for detoxification: complexation between aconitine and liquiritin in a Chinese herbal formula ('Sini Tang')

ETHNOPHARMACOLOGICAL RELEVANCE

Sini Tang (SNT) is a traditional Chinese herbal formulation consisting of three different herbs: Aconitum carmichaelii (Fuzi), Zingiber officinale (Ganjiang), and Glycyrrhiza uralensis (Gancao). For this study, we modified this mixture by adding the bark of Cinnamomum cassia (Rougui, ). Aconitum carmichaelii contains aconitine and its derivatives, all of which are highly toxic alkaloids. These compounds are commonly detoxified with pyrolytic and hydrolytic pretreatments, such as Heishunpian, which requires repeated soaking in salt water, boiling until the roots turn black, and drying in the oven. We now demonstrate that Glycyrrhiza uralensis, which is often used in Traditional Chinese Medicine for detoxification, reduces the concentration of free aconitine in decoctions by forming a complex between liquiritin and aconitine.

MATERIALS AND METHODS

Aqueous extracts of SNT, each individual herb or herbal mixture, and methanolic extracts of individual herbs were tested for free aconitine by HPLC coupled with a diode array detector. A detected complex was investigated by NMR and UV/vis spectroscopy. The continuous variations method and (1)H-NMR titrations provided the complex stoichiometry and binding constant. A 2D-ROESY experiment was performed to obtain the structural details of the formed complex.

RESULTS

A fast and simple HPLC method was developed to determine the amounts of aconitine and its derivatives found in herbal extracts. The Heishunpian pretreatment led to nearly complete pyrolysis and hydrolysis of the toxic compounds. However, in some batches, considerable amounts of aconitine remained. The addition of Glycyrrhiza uralensis to Aconitum carmichaelii, or liquiritin to free aconitine, led to a complexation with aconitine. The complex possessed a 1:1 stoichiometry and a binding constant of ca. 3000 L/mol to 4000 L/mol in mixtures of aqueous methanol.

CONCLUSIONS

A new HPLC based method allows the concentration of toxic aconitine and other diester diterpene alkaloids in herbal extracts to be rapidly determined. This method provides a starting point for the development of routine quality control procedures. The complexation of free aconitine by adding an excess of Glycyrrhiza uralensis or free liquiritin to SNT formulations will make these formulations safer.

[Determination of aconitine, hypaconitine and mesaconitine in Shenfu injection]

To establish a method for the content determination of indexes for measuring aconitic compounds contained in Shenfu injection, in order to provide basis for the evaluation of the curative effect of monkshood in Shenfu injection. The sample were purified and enriched with HF-LPME. ACQUITY UPLC BEH C18 column (2.1 mm x 50 mm, 1.7 microm) was adopted and eluted with a gradient program, with acetonitrile-10 mmol x L(-1) NH4HCO3 (pH 10) as the mobile phases. The flow rate was 0.45 mL x min(-1). The content was determined with ESI and MRM. The results showed that aconitine, hypaconitine and mesaconitine showed a good linear relationship, with r > 0.999, within the range of 0.1-100 ng x L(-1). The recoveries were detected to be 100.1%, 97.4%, 97.5%, with RSD being 1.2%, 1.1%, 1.5%, respectively. This method was used to prove the safety of Shenfu injection, and provide scientific basis for correct evaluation of curative effect of monkshood, as well as a reliable, simple and practical means for quality control of monkshood-containing Chinese materia medica preparations.

UPLC-Q-TOF-HDMS analysis of constituents in the root of two kinds of Aconitum using a metabolomics approach

INTRODUCTION

Metabolomics is an 'omics' approach that aims to comprehensively analyse all metabolites in a biological sample, and has great potential for directly elucidating plant metabolic processes. Increasing evidence supports the view that plants produce a broad range of low-molecular-weight secondary metabolites responsible for variation from species to species, thus enabling the use of secondary metabolite profiling in the chemotaxonomy.

OBJECTIVE

To gain deeper insights into the metabolites to increasing plant diversity, we performed systematic untargeted metabolite profiling to exploit the different parts and species of Aconitum as a case study.

METHOD

Application of ultraperformance liquid chromatography-quadrupole time-of-flight-high-definition mass spectrometry (UPLC-QTOF-HDMS) equipped with electrospray ionisation and coupled with pattern recognition analyses to study constituents in the root of two kinds of Aconitum species.

RESULTS

Twenty-two metabolites between the mother root of Aconitum carmichaelii Debx (CHW) and lateral root of Aconitum carmichaelii Debx (SFZ) and 13 metabolites between the CHW and root of Aconitum kusnezoffii Reichb (CW) have been identified. Of note, songorine, carmichaeline and isotalatizidine did not exist in CW, whereas they are present in the SFZ and CHW.

CONCLUSION

Metabolomics based UPLC-QTOF-HDMS with multivariate statistical models was effective for analysis of constituents in the root of two kinds of Aconitum species.

[Rationality of the processing methods of aconiti lateralis radix (Fuzi) based on chemical analysis]

In this study, we explored the rationality of processing methods and mechanism of Aconiti Lateralis Radix (Fuzi) through comparing the chemical contents of diester alkaloids (DAs) and monoester alkaloids (MAs) in the raw material of Fuzi and its processed products. The results showed that the toxicity potency of MAs is at least lower than 1/64 to 1/180 of the toxicity potency of DAs. The contents of DAs in processed Fuzi decreased to 1/76.5 to 1/38.3 of the value of raw Fuzi. The contents of MAs in processed Fuzi significantly increased by 4.6 to 5.2 fold or basically the same as that of the raw Fuzi. The values of MAs/DAs of processed Fuzi were enhanced by 30 to 390 fold of the raw Fuzi. It was found that the contents of DAs were insignificantly different between "Wu dan fu pian" (steaming or stir-frying without Danba) and "Dan fu pian" (steaming or stir-frying with Danba). The result suggested that the abilities of "eliminating toxicity" of different processing methods were equivalent at all. In contrast, the contents of MAs contained in "Wu dan fu pian" were of 5.3 to 8.7 fold higher than the values in "Dan fu pian". This result suggested the processing method by steaming or stir-frying without Danba might have better effect for "conserving property" than the method processed with Danba stipulated by China Pharmacopoeia. We believe that the new processing method without Danba can be recommended in further application due to it offers a simple procedure and it will not introduce inorganic impurities in the products.

Cladosporium cladosporioides XJ-AC03, an aconitine-producing endophytic fungus isolated from Aconitum leucostomum

The endophytic fungus XJ-AC03, which was isolated from the healthy roots of Aconitum leucostomum, produced aconitine when grown in potato dextrose agar (PDA) medium. The presence of aconitine was confirmed by the chromatographic and spectroscopic analyses. The yield of aconitine was recorded as 236.4 μg/g by high performance liquid chromatography (HPLC). The mass spectrometry was shown to be identical to authentic aconitine. Further analysis with nuclear magnetic resonance (NMR) spectroscopy to show the chemical structure of the fungal aconitine indicated that the fungal aconitine produced an NMR spectrum identical to that of authentic aconitine. Strain XJ-AC03 was identified as Cladosporium cladosporioides by its characteristic culture morphology and ITS rDNA sequence analysis.

Identification and determination of Aconitum alkaloids in Aconitum herbs and Xiaohuoluo pill using UPLC-ESI-MS

A rapid, specific, and sensitive ultra-performance liquid chromatography-electrospray ionization-mass spectrometry (UPLC-ESI-MS) method to examine the chemical differences between Aconitum herbs and processed products has been developed and validated. Combined with chemometrics analysis of principal component analysis (PCA) and orthogonal projection to latent structural discriminate analysis, diester-diterpenoid and monoester-type alkaloids, especially the five alkaloids which contributed to the chemical distinction between Aconitum herbs and processed products, namely mesaconitine (MA), aconitine (AC), hypaconitine (HA), benzoylmesaconitine (BMA), and benzoylhypaconitine (BHA), were picked out. Further, the five alkaloids and benzoylaconitine (BAC) have been simultaneously determined in the Xiaohuoluo pill. Chromatographic separations were achieved on a C₁₈ column and peaks were detected by mass spectrometry in positive ion mode and selected ion recording (SIR) mode. In quantitative analysis, the six alkaloids showed good regression, (r) > 0.9984, within the test ranges. The lower limit quantifications (LLOQs) for MA, AC, HA, BMA, BAC, and BHA were 1.41, 1.20, 1.92, 4.28, 1.99 and 2.02 ng·mL⁻¹, respectively. Recoveries ranged from 99.7% to 101.7%. The validated method was applied successfully in the analysis of the six alkaloids from different samples, in which significant variations were revealed. Results indicated that the developed assay can be used as an appropriate quality control assay for Xiaohuoluo pill and other herbal preparations containing Aconitum roots.

Reaction product analysis of aconitine in dilute ethanol using ESI-Q-ToF-MS

The study was done to identify the reaction products of aconitine in dilute ethanol using electrospray ionization-triple quad time-of-flight mass spectrometry (ESI-Q-TOF-MS). Five hydrolysates were detected, their pseudo-molecules are 632, 604, 586, 570, 500, they are 8-ethyoxyl-14-benzoylaconitine, benzoylaconine, pyraconitine, 8-acetyl-14-ethyoxylaconitine, aconine, respectively. Among them, 8-ethyoxyl-14-benzoylaconitine and 8-acetyl-14-ethyoxylaconitine were identified firstly as reaction products of aconitine in dilute ethanol, and can thus be used as indicators in quality control of medicinal Aconitum preparations used in Traditional Chinese Medicine.

[Simultaneous determination of four components in sini tang by HPLC]

OBJECTIVE

To develop an HPLC method for determining four components in Sini Tan, benzoylmesaconine, liquiritin, glycyrrhizic acid and 6-gingerol.

METHOD

The Hypersil BDS column was adopted with gradient elution program at a flow rate of 1.0 mL x min(-1) and the detection wavelength of 235 nm.

RESULT

Benzoylmesaconine, liquiritin, glycyrrhizic acid and 6-gingerol showed good separation, with the linear range of 0.006-0.12, 0.021-0.42, 0.012-0.24 and 0.018-0.36 g x L(-1), respectively. Their average recoveries were 99.3%, 96.9%, 100% and 100%, respectively; and RSD of the above four components were 1.5%, 0.6%, 1.3% and 2.1%, respectively.

CONCLUSION

The method is proved to be so easy and accurate and practical that it can be used to determine the four components in Sini Tang.

[UPLC-TOF/MS based chemical profiling approach to evaluate toxicity-attenuated chemical composition in combination of ginseng and radix aconiti praeparata]

In the present study, an ultra performance liquid chromatography coupled with time-of-fight mass spectrometry (UPLC-TOF/MS) based chemical profiling approach was used to evaluate chemical constitution between co-decoction and mixed decoction of ginseng and Radix Aconiti Praeparata. Two different kinds of decoctions, namely co-decoction of ginseng and Radix Aconiti Praeparata: water extract of mixed two herbs, and mixed decoction of ginseng and Radix Aconiti Praeparata: mixed water extract of each individual herbs, were prepared. Batches of these two kinds of decoction samples were subjected to UPLC-TOF/MS analysis. The datasets of t(R) m/z pairs, ion intensities and sample codes were processed with supervised partial least squared discriminant analysis (OPLS-DA) to holistically compare the difference between these two decoction samples. Significant difference between the two decoction samples was showed in the results of positive ion mode. The contents of hypaconitine and deoxyaconitine decreased, while that of benzoylmesaconine, benzoylhypaconine and dehydrated benzoylmesaconine increased in the samples of co-decoction of ginseng and Radix Aconiti Praeparata. The content of diester-diterpenoid alkaloids decreased, while that of monoester-diterpenoid alkaloids increased, which is probably the basis of toxicity-attenuated action when combined ginseng with Radix Aconiti Praeparata.

[Determination of content changes of three diester-diterpenoid alkaloids in compatibility of radix aconiti laterlis preparata and Rhizoma pinelliae, Fructus trichosanthis, Bulbus fritillariae, Radix ampelopsis, Rhizoma bletillae by HPLC]

OBJECTIVE

To analyze the three diester-alkaloids content in the decoctions before and after Radix aconiti lateralis preparata combined with Rhizoma pinelliae, Fructus trichosanthis, Bulbus fritillariae, Radix ampelopsis, Rhizoma bletillae, respectively.

METHODS

HPLC analysis was performed on a Agilent Extend C18 column,eluted with a mobile phase consisted of acetonitrile/methanol - 35 mmol/L ammonium acetate and gradient elution,with a flow rate of 0.6 ml/min and the detection wavelength of 235 nm.

RESULTS

The contents of three diester-alkaloids in the co-decoctions of Radix aconiti laterlis preparata combined with Rhizoma pinelliae, Fructus trichosanthis, Bulbus fritillariae, Rhizoma bletillae were more than that of single Radix aconiti laterlis preparata decoction, expect the Bulbus fritillariae cirrhosae,Radix ampelopsis and Rhizoma pinelliae praeparatum. From the result,we can found that the content of three diester-alkaloids in decoctions was correlated with the decoction pH.

CONCLUSION

The pH of decoction is one of the most important factors to relate the three diester-alkaloids content in the decoctions.

[Extraction technology of diester-type alkaloids from Radix Aconiti lateralis]

OBJECTIVE

To determine the suitable extraction technology of diester-type alkaloids, such as mesaconitine, aconitine and hypaconitine from the roots of Aconitum carmichaeli (Radix Aconiti lateralis).

METHODS

The contents of mesaconitine, aconitine and hypaconitine were determined by HPLC. Single-factor experiment was used to study the extraction factors.

RESULTS

The suitable extraction technology for diester-type alkaloids was as follows: coarse sizings of Radix Aconiti lateralis was extracted by 10 times ethanol for 3 times (each time for 1 day) at 15 degrees C. The total yield of diester-type alkaloids was 0.57%, including 0.16% aconitine, 0.032% mesaconitine and 0.38% hypaconitine, and the purity was 18.81%.

CONCLUSION

The extraction technology is efficient, harmfulless, economical, convenient and can be used for industrial production.

Lappaconitine-loaded microspheres for parenteral sustained release: effects of formulation variables and in vitro characterization

Lappaconitine instead of its hydrobromide salts has been encapsulated in poly (lactide-co-glycolide) acid (PLGA) microspheres by the simple o/w emulsion solvent evaporation technique. The effects of several variables including emulsifier (polyvinyl alcohol, PVA) concentration, stirring speed, PLGA concentration and drug/polymer mass ratios on quality of microspheres have been investigated. The particle size and size distribution can be controlled by PVA concentration, stirring speed and PLGA concentration. The entrapment efficiency and the burst release of lappaconitine from drug-loaded microspheres were dominantly affected by the drug/polymer mass ratio and PVA concentration. The best parameters of formulation were 1.5% PVA, the PLGA concentration of 50 g/L, and the stirring speed of 800 rpm and drug/polymer of 1:5. The optimized formulation has a mean particle size of 19.3 +/- 0.93 microm, mean entrapment efficiency of 70.77 +/- 3.23% and mean drug loading of 11.45 +/- 0.47%. Based on the optimized parameters of formulation, the effects of oil/aqueous solubility partition ratio of drug on entrapment efficiency of drug-loaded microspheres prepared by o/w emulsion solvent evaporation were further studied. A good linear relation existed between the partition ratio and entrapment efficiency. The optimized microspheres were characterized by SEM, FT-IR, DSC and XRD. SEM shows spherical and smooth surface and uniform size distribution. The results of DSC, FT-IR study reveal no interaction between drug and polymer. The results of the XRD study indicate lappaconitine trapped in microsphere exists in form of an amorphous or disordered crystalline status in polymer matrix. The in vitro release models were evaluated with two different groups of drug-loaded microspheres including microspheres washed with distilled water and 0.01N HCL, respectively. The drug release profile of lappaconitine-loaded microspheres washed with distilled water agreed with zero order equation and that of the latter better agreed with first order equation.

[Determination of aconitine and hypaconitine in Gucixiaotong Ye by capillary electrophoresis with field-amplified sample injection]

OBJECTIVE

To set up a capillary electrophoresis method with field-amplified sample injection for the determination f aconitine and hypaconitine in Gucixiaotong Ye.

METHOD

An uncoated fused-silica capillary column (50 microm x 50 cm, effective length 42 cm) was used as the separation channel. The running buffer was 50 mmol x L(-1) phosphate electrolyte solution (pH 9)-m nol (90:10) , the running voltage was 10 kV and the capillary inlet was dipped in methanol for 5 s prior to electrokinetic injection (12 kV, 30 s), the detection wavelength was set at 235 nm.

RESULT

Aconitine and hypaconitine were linear in the concentration ranges of 17.2-275 microg x L(-1) and 34. 4-550 microg x L(-1), respectively. The average recovery was more than 93.9% with the RSD of 3.8%. This method could enrich 500 fold of aconitine alkaloid.

CONCLUSION

The method is simple, rapid and specific with high stacking efficiency, it provides a new reliable means for production and quality control of Gucixiaotong Ye.

[Analysis of chemical composition in the combination of monkshood and pinellia by UPLC/Q-TOFMS with multivariate statistical analysis]

In the present study, an ultra performance liquid chromatography coupled with time-of-flight mass spectrometry (UPLC/Q-TOFMS) based on chemical profiling approach to evaluate chemical constitution between mixed decoction and co-decoction of monkshood-pinellia combination of the eighteen incompatible medications (Shi Ba Fan) was proposed. Two different kinds of decoctions, namely monkshood-pinellia co-decoction: water extract of the two herbs together, and monkshood-pinellia mixed decoction: water extract of each individual herbs mixed together, were prepared. Batches of these two kinds of decoction samples were subjected to UPLC/Q-TOFMS analysis, the datasets were processed with MassLynx 4.1 to holistically compare the difference between these two kinds of decoction samples. The most changed components during decocting were analyzed. Using the proposed approach, global chemical difference was found between co-decoction and mixed decoction, mesaconitine, aconitine and hypaconitine were identified as the most changed components (changed most significantly) during decocting. Result shows significant difference between two kinds of decoction samples, and the significant differences are probably related to the incompatibility of monkshood and pinellia.

[Evaluation of the accumulation of dry substance and active componentsevaluation of the accumulation of dry substance and active components of Radix Aconiti Lateralis Praeparata]

OBJECTIVE

To study the accumulation rules of dry substance and active components in the Radix Aconiti Lateralis Praeparata for providing the basic evidences to collection time.

METHODS

The Roots were collected periodically and their fresh weight and dry weight were measured. The contents of total alkaloids and three diester aconitum alkaloids aconitine, hypaconitine and mesaconitine were determined by titration and HPLC respectively.

RESULTS

During the stage of root inflation, the content of total alkaloids was at a certain level, while the content of diester aconitum alkaloids were increased gradually. The total amount of alkaloid and diester aconitom alkaloids were increased rapidly from the last third of April to the middle third of June, and then maintained at relative constant levels and were decreased from the first third of July.

CONCLUSION

It is more preferable to collect the Radix Aconiti Lateralis Praeparata during the period from the last third of June to first third of July.

Development and validation of a rapid capillary zone electrophoresis method for the determination of aconite alkaloids in aconite roots

INTRODUCTION

Aconites, with aconite alkaloids as the major therapeutic and toxic components, are used for the treatment of analgesic, antirheumatic and neurological symptoms. Quantification of the aconite alkaloids is important for the quality control of aconite-containing drugs.

OBJECTIVE

To establish a validated capillary zone electrophoresis (CZE) method for the simultaneous determination of six major alkaloids, namely aconitine, mesaconitine, hypaconitine, benzoylaconine, benzoylmesaconine and benzoylhypaconine, in crude and processed aconite roots.

METHODOLOGY

The CZE method was optimised and validated using a stability-indicating method. The optimised running buffer was a mixture of 200 mm Tris, 150 mm perchloric acid and 40% 1,4-dioxane (pH 7.8) with the capillary thermostated at 25 degrees C.

RESULTS

Using the optimised method, six aconite alkaloids were well separated. The established method showed good precision, accuracy and recovery. Contents of these alkaloids in crude and processed aconites were determined and it was observed that the levels of individual alkaloids varied between samples.

CONCLUSION

The developed CZE method was reliable for the quality control of aconites contained in herbal medicines. The method could also be used as an approach for toxicological studies.

[Study on processing principle of Aconitum pendulum]

OBJECTIVE

To study the processing principles of different processed products of Aconitum pendulum.

METHOD

Using high performance liquid chromatography and acute toxicity test to compare the changes in chemical composition and toxicity of the roots and processed products of A. pendulum.

RESULT

The main toxic components of the roots of A. pendulum were aconitine, deoxyaconitine and 3-acetylaconitine. The contents of these three alkaloids were significantly reduced in processed products, while benzoylaconitine significantly increased. In addition, processed products emerged aconine, polyschistine-D, beyzoyldeoxyaconine, 16-epi-pyroaconitine and 16-epi-pyrodeoxyaconitine. From the structural analysis, these new emerged compounds transformed from the aconitine, deoxyaconitine and 3-acetylaconitine.

CONCLUSION

Different processing methods can reduce the toxicity of the roots of A. pendulum. Processing principle is ester hydrolysis and high-temperature pyrolysis.

Analytical aspects of diterpene alkaloid poisoning with monkshood

A sensitive and specific method for aconitine extraction from biological samples was developed. Aconitine, the main toxic alkaloid from plants belonging to Aconitum species (family Ranunculaceae), was determined in plant material by an external standard method, and by a standard addition calibration method in biological fluids. Described here is one fatal case and five intoxications of accidental aconitine poisoning following the ingestion of aconite mistaken for an edible grass, Aruncus dioicus (Walt.) Fernald, "mountain asparagus", and Cicerbita alpina (L.) Wallroth. The aconitine content in urine was in the range 2.94 microg/mL (dead patient)-0.20 microg/mL (surviving patients), which was almost two to four times higher than that in plasma.

Selective determination of aconitine in polyherbal oils containing Aconitum chasmanthum using high-performance thin-layer chromatography

Many polyherbal oil formulations in traditional systems of medicine contain aconite root. This paper reports the development and validation of a simple, rapid, and sensitive HPTLC method for identification and quantification of aconitine from polyherbal oil formulations. Chromatography of methanolic extract of these formulations was performed on silica gel 60F254 aluminum-backed HPTLC plates with a 0.2 mm layer thickness. The plates were developed up to 85 mm with the binary mobile phase ethyl acetate-ethanol (7.5 + 2.5, v/v) at 22 +/- 2 degrees C with 20 min of chamber saturation. The system produced a compact band of the marker aconitine at an R(f) value of 0.33 that was quantified at its maximum absorbance of 238 nm. The LOD and LOQ values were found to be 20 and 70 ng/band, respectively. The linearity with respect to peak area was in the range of 300 to 1800 ng/band with an r of 0.9991. Polyherbal oil formulations were analyzed with reasonable accuracy, and no matrix interference was observed. The developed HPTLC method is accurate, precise, and cost-effective, and can be used for marker-based QA of polyherbal oil formulations containing Aconitum chasmanthum as one of the active ingredients.

Stability-indicating reversed-phase liquid chromatographic methods for the determination of aconitine and piperine in a polyherbal formulation

Simple and rapid stability-indicating HPLC methods were developed for the individual analysis of aconitine (ACN) and piperine (PIN) in Mahamrutynjaya rasa, an herbal dosage form containing Aconitum ferox, Piper nigrum, and Piper longum in combination. Separation of the ACN from its major and minor degradation products was successfully achieved on a reversed-phase C18 column (250 x 4.6 mm id, 5 microm particle size), with isocratic elution using a mixture of acetonitrile-KH2PO4 buffer (10 mM, pH 8 +/- 0.1; 50 + 50, v/v) at flow rate of 0.7 mL/min with UV detection at 227 nm. PIN separation was performed on a reversed-phase C18 column (250 x 4.6 mm id, 5 microm particle size), with isocratic elution in acetonitrile-KH2PO4 buffer (10 mM, pH 7 +/- 0.1; 35 + 65, v/v) at a flow rate of 1 mL/min with UV detection at 343 nm. The methods were validated with respect to linearity, precision, accuracy, specificity, system suitability, and robustness. The responses were linear in the drug concentration range of 10-100 microg/mL for both ACN and PIN. The percent recoveries of both the markers from a mixture of degradation products were in the range between 98-101%. The utility of the procedures was verified by their application to marketed formulations that were subjected to accelerated degradation studies. The methods could distinctly separate the drug and degradation products. The products formed in the marketed tablets were similar to those formed in the laboratory during stress studies.

A rapid resolution liquid chromatographic method for fingerprint analysis of raw and processed caowu (Aconitum kusnezoffii)

A sensitive and reliable rapid resolution liquid chromatographic (RRLC) method coupled with diode array detection has been developed for the fingerprint analysis of raw and processed caowu (Aconitum kusnezoffii). The RRLC fingerprints were established with a Zorbax Extend C18 analytical column (4.6 x 50 mm, 1.8 microm) and gradient elution. Analysis run time was <10 min. The method displayed good precision, stability, and repeatability in fingerprint analysis. Characteristic RRLC fingerprints of caowu were generated and used to assess the consistency and differences in the products. Raw and processed caowu from different sources were analyzed under the developed RRLC conditions, yielding contrasting RRLC fingerprints. Comparison of the RRLC fingerprints of processed and raw caowu indicated that the major constituents changed during processing. Meanwhile, a peak area ratio analysis method was applied to assess their chromatographic fingerprints. In characterizing the constituents of caowu, 11 major chromatographic peaks were identified by mass spectrometry and compared with reference standards and reference data. In summary, RRLC fingerprinting is a rapid and useful way to evaluate the quality of raw and processed caowu.

Qualitative and quantitative analysis of aconitine-type and lipo-alkaloids of Aconitum carmichaelii roots

By optimizing the extraction and analytical conditions, a reliable and precise HPLC method coupled with photodiode array detection (HPLC-DAD) has been developed for the identification and quantification of three major aconitine-type alkaloids (aconitine, mesaconitine, hypaconitine) in the roots of Aconitum carmichaelii Debeaux. The qualitative analysis of the plant material was carried out by LC-APCI-MS(n). By means of this method, 26 lipo-alkaloids were also identified from the roots of A. carmichaelii. The effect of processing on aconitine-type alkaloids, lipo-alkaloids and pure aconitine was studied. As part of our investigation, two lipo-alkaloids, 14-benzoylaconine-8-palmitate and 14-benzoylaconine-8-linoleate were produced semisynthetically. The COX-1, COX-2 and LTB(4) formation inhibitory activity of aconite root extracts and different types of diterpene alkaloids and the toxicity of lipo-alkaloids were also investigated.

Determination of aconitine-type alkaloids as markers in fuzi (Aconitum carmichaeli) by LC/(+)ESI/MS(3)

LC/(+)ESI/MS(3) was used to determine aconitine, mesaconitine, and hypaconitine as target markers in crude methanol extracts of (i) the raw lateral roots of Aconitum carmichaeli, (ii) roots treated by three different refining processes, and (iii) eight generally available traditional Chinese medicine (TCM) preparations containing fuzi (treated lateral roots of A. carmichaeli). The optimal ionization behavior resulted when using electrospray ionization (ESI) in positive-ion mode with 0.005% TFA as an additive in the mobile phase. The consecutive reaction monitoring (CRM) mode provided additional improvements in selectivity, which was exploited to minimize the noise and interference problems. Employing this approach, aconitine and mesaconitine were found to decompose readily during the refining processes, but hypaconitine remains present at the same content, presumably because of its characteristic chemical structure. Thus, treated and untreated fuzi samples can be distinguished by monitoring the ratio of aconitine and mesaconitine to hypaconitine. The limits of detection (LODs) for these three markers were 0.05, 0.08, and 0.03 ng/ml. The linearity range for the three marker compounds was 0.1-1,000 ng/ml. The analysis time was 12 min per sample.

[Limited determination of trace toxical aconitine alkaloid in guifudihuang pills]

OBJECTIVE

To establish a capillary electrophoresis with field-amplified sample stacking method for the separation and determination of aconitine alkaloid in Guifudihuang pills.

METHOD

An uncoated fused-silica capillary column (50 microm x 43 cm, effective length 35 cm) was used. The running buffer was 50 mmol x L(-1) phosphate electrolyte solution (pH 4.6)-methanol (8:2). The runing voltage was 10 kV and the capillary inlet was dipped in methanol for 5 s prior to electrokinetic injection (10 kV, 40 s). The detection wavelength was 235 nm.

RESULT

This method allowed 500 fold enrichment of aconitine alkaloid. A good linear relation was obtained in the range of 31.3-2 x 10(3) microg x L(-1) (r = 0.9996), with the detection limit of 9.4 microg x L(-1). The average recovery was 98.0% with the RSD of 2.6%.

CONCLUSION

The method is simple, rapid and specific with high stacking efficiency; it provides a new reliable means for production and quality control of Guifudihuang pills.

[Study on the optimum extracting conditions of total alkaloids and aconitine in Aconitum szechenyianum Gay]

OBJECTIVE

To optimize the conditions for extractions of total alkaloids and aconitine from Aconitum szechenyianum Gay.

METHODS

Using L16 (4(5)) orthogonal test and univariant methods, the exrtaction conditions of total alkaloids aconitine in Aconitum szechenyianum Gay. were optimized under the guidance of the content determination of total alkaloids with bromophemol blue colorimetry and aconitine with HPLC method, respectively.

RESULTS

The obtained optimum condition of total alkaloids was that the material was refluxed in 6 times (m/v) acidic alcohol solution( alcohol: pH 3.0 HAc = 85:15, v/v) for 1 h with 3 times. The condition of aconitine was that the material was refluxed in 4 times (m/v) acidic alcohol solution (alcohol: pH 3. p HAc = 15:85, v/v) for 0.5 h with 3 times. Contents of total alkaloids and aconitine in Aconitum szechenyianum Gay. were 0.980% and 0.109%, respectively.

CONCLUSION

Through the test and verify, the optimum extraction methods of total alkaloids and aconitine are rational.

[Study on separation and purification of total alkaloids and mesaconitine with X - 5 macroporous resin]

OBJECTIVE

To study systematically the factors which affect separation and purification of the total alkaloids and mesaconitine with X -5 macroporous resin.

METHOD

With the content of the total alkaloids and mesaconitine as parameters, the optimum condition of absorption and elution were studied in the process of the purification with X -5 macroporous resin.

RESULT

The X - 5 macroporous resin yielded the best separating efficiency when the concentration of the extracted solution was 1 g raw material per 1 mL, pH 12.0, the absorptive time of 6 hour and the volume of 95% ethanol (7BV pH 8) as the eluant; X -5 macroporous resins was used five times in a reproducible way. The rate of extraction and content of the total alkaloid were 80% and 30% respectively after purification with X - 5 macroprous resin.

CONCLUSION

The method can increase the purity of mesaconitine and total alkaloids.

[Analysis of aconite alkaloids in the combination of radix aconiti lateralis preparata with different herbs by ESI-MS spectrometry]

The method was established study the influence of different herbal combination with Radix Aconiti in the traditional medical formulae on content of the aconite alkaloids, for elucidating the scientific basis of reducing the toxicity of aconite in traditional Chinese medical formulation. The samples for ESI-MS study were prepared by decocting a mixture of Radix Aconiti Lateralis Preparata ( RALP) with Radix Glycyrrhizae Preparata (RGP) , Radix Paeoniae Alba ( RPA) , Rhizoma Zingiberis (RZ) or Radix Et Rhizoma Rhei ( RERR) , separately, and extracting the residue of the above mentioned mixtures after decocting. The diester-diterpenoid alkaloids (DDAs) was lower in the herb couples of RALP-RGP, RALP-RPA, RALP-RZ and RALP-RERR, and lipo-alkaloids was increased in the herb couples of RALP-RGP, RALP-RPA and RALP-RZ. The reason of reducing toxic effect principle is that the components of RGP, RPA and RZ have ester-exchange reactions with DDAs in RALP to produce lipo-alkaloids of low toxicity in the decocting process of the herb couples. The combination of RALP-RERR can reduce the content of DDAs in decoction and residue due to the formation of water insoluble alkaloid compound.

Combinative method using HPLC quantitative and qualitative analyses for quality consistency assessment of a herbal medicinal preparation

A selective and efficient quality consistency assessment system was developed for monitoring the manufacturing processes of a Chinese herbal preparation, qingfu guanjieshu (QFGJS) capsule, and for assessing its stability over time. This system is based on quantitative determination of four marker compounds, i.e., sinomenine, paeoniflorin, paeonol, and curcumin, and on qualitative fingerprinting analysis of QFGJS using high-performance liquid chromatography-photodiode array detection (HPLC-DAD) method. The separation was performed on a Phenomenex ODS column by gradient elution with acetonitrile and aqueous phase (containing 0.1% phosphoric acid, adjusted with triethylamine to pH 3.5+/-0.2) at a flow-rate of 1.0 ml/min. In fingerprinting analysis, the chemical characteristics of four herbs present in QFGJS (excluding radix Aconiti Lateralis Preparata) were present in the HPLC chromatographic file. In addition, quantitative determination of hypaconitine was carried out with our published HPLC method as a supplement for quality control of the radix Aconiti Lateralis Preparata in QFGJS. The results showed that the contents of these five marker compounds and HPLC fingerprint profiles of three batches of QFGJS products collected at 3 months after production in the stability testing were relatively consistent. This well-developed method could be used for quality assessment of the complex preparations of herbal medicine.

Characterization of metabolites and cytochrome P450 isoforms involved in the microsomal metabolism of aconitine

Aconitine, a major Aconitum alkaloid, is well known for its high toxicity that induces severe arrhythmias leading to death. The current study investigated the metabolism of aconitine and the effects of selective cytochrome P450 (CYP) inhibitors on the metabolism of aconitine in rat liver microsomes. The metabolites were separated and assayed by liquid chromatography-ion trap mass spectrometry (LC/MS(n)) and further identified by comparison of their mass spectra and chromatographic behaviors with reference substances. Various selective inhibitors of CYP were used to identify the isoforms of CYP, that involved in the metabolism of aconitine. A total of at least six metabolites were found and characterized in rat liver microsomal incubations. Result showed that the inhibitor of CYP 3A had an inhibitory effect on aconitine metabolism in a concentration-dependant manner, the inhibitor of CYP1A1/2 had a modest inhibitory effect, whereas inhibitors of CYP2B1/2, 2D and 2E1 had no obvious inhibitory effects on aconitine metabolism. Aconitine might be metabolized by CYP 3A and CYP1A1/2 isoforms in rat liver microsome.

Aconitine involvement in an unusual homicide case

We describe a homicide complicated by an aconitine poisoning, which was initially thought to be a strangulation case. Routine toxicological analyses demonstrated only a small amount of alcohol in the blood and the urine. The case could not be clarified until 5 years after the event. A new element in the investigation made the wife the prime suspect, and finally, after thorough interrogation, she confessed her crime. She had mixed a decoction of three plants of Aconitum with red wine. Additional toxicological analyses, using the liquid chromatography-tandem mass spectrometry (LC-MS-MS) technique demonstrated 810 ng/ml of aconitine in urine, 6.5 ng/g in liver and 1.3 ng/g in the kidneys. Even though aconitine poisoning is still rare in Europe, it should be taken into account in suicides and homicides, particularly in unclarified cases.

HPLC-UV method for nicotine, strychnine, and aconitine in dairy products

The toxic nitrogen alkaloids nicotine, strychnine, and aconitine were quantitated in whole milk, skim milk, and cream using solid-phase extraction cleanup and HPLC-UV with dual wavelength detection. Samples were extracted in McIlvaine's buffer with EDTA and then partitioned with aqueous acetonitrile and hexane. The aqueous phase was concentrated and passed through an OASIS HLB column. The column was eluted with methylene chloride/ammonium hydroxide, 1 mL/1 microL, v/v. The eluent was acidified with hydrochloric acid and evaporated. The sample was diluted for HPLC with acetonitrile/phosphate buffer pH 7.4. Chromatography was performed on an Xterra RP-18 column using a gradient of acetonitrile and ammonium bicarbonate buffer at pH 9.8. Nicotine and strychnine were monitored at 260 nm; aconitine was monitored at 232 nm. Calibration curves were generated from external standards in the range 0.2-10 microg/mL using 1/x weighting. Mean recoveries in whole milk spiked between 0.1 and 10 ppm were the following: nicotine 89.2%, strychnine 75.7%, and aconitine 85.1%. Mean recoveries in skim milk spiked between 0.1 and 10 ppm were the following: nicotine 72.1%, strychnine 78.2%, and aconitine 82.9%. Mean recoveries in cream spiked between 0.2 and 20 ppm were the following: nicotine 87.9%, strychnine 76.9%, and aconitine 82.0%. Relative standard deviations of recovery were less than 20% in each case.

[Experimental approach to murder by aconite poisoning from the viewpoint of medicolegal toxicology]

An autopsy case performed by the author in 1986 had been gradually revealed to be a murder using aconite poisons. The puffer fish toxin was certified afterwards to be co-administered together with aconite alkaloids in this case. In order to investigate this murder case, animal experiments were done using mice to clarify the metabolism of aconitine and tetrodotoxin, and to examine the influences of tetrodotoxin on aconite poisoning. We also examined biological effects under the chronic intoxication of aconitine, and the elimination and degradation of aconitine in dead body. For this purpose we have developed technical methods using GC/MS and LC/MS for the quantification of these toxins in biological materials.

[Determination of three kind of diester diterpenoid alkaloids (DDAs) in Aconitum carmichaeli and its processed products by HPLC]

OBJECTIVE

To establish an HPLC method for the determination of three kind of diester diterpenoid alkaloids (DDAs) in Aconitum carmichaeli and its processed products namely mesaconitine, aconitine and hypaconitine.

METHOD

A Zorbax Eclipse XDB C18 column was used, and ammonium acetate solution-acetonitrile as the mobile phase, with a flow rate of 1.0 mL x min(-1) and a detection wavelength of 230 nm.

RESULT

Mesaconitine, aconitine and hypaconitine, were separated, and the calibration curves of them were in good linearity over the range of 0.035 7-1.784 microg (r = 0.9999), 0.0126-0.632 microg (r = 0.9997) and 0.0334-1.672 microg (r = 0.9997) respectively.

CONCLUSION

This method is simple and accurate. It can be used in the identification and quality control of A. carmichaeli.

[Studies on HPLC fingerprint of Radix Aconiti Kusnezoffii]

OBJECTIVE

To establish the HPLC fingerprint of Radix Aconiti Kusnezoffii.

METHOD

The chromatographic separation was performed on a Kromasil C18 (4.6 mm x 250 mm, 5 microm) eluted with a mobile phase of acetonitrile-ammonium acetate buffer (2. 5 per thousand acetic acid-ammonia pH 10.5) (60:40). The UV detection wavelength was set at 240 nm and the flow rate was set at 1.0 mL x min(-1).

RESULT

The RSD of precision and repeatability was less than 2%. Under the selected chromatographic conditions, good HPLC fingerprints of Radix Aconiti Kusnezoffii were obtained.

CONCLUSION

The method was simple, accurate and repeatable. It can be used for the quality control of Radix Aconiti Kusnezoffii.